[R] Problems outputting ggplot2 graphics to pdf

[Ulrik Stervbo]

Hi Hugh,

I believe the recommended way of saving ggplots is through ggsave. It
defaults to take the latest plot displayed, but you can specify which plot
to save by passing the variable to the plot argument.

If you need to save multiple plots in one file, you have to create a
multipage plot using gridExtra::marrangeGrob.

Best wishes,
Ulrik

On Thu, 2 Mar 2017 at 14:53 Hugh Morgan <h.morgan at har.mrc.ac.uk> wrote:

> Thanks for the help.  My test script was changed with:
>
> p <- ggplot(df, aes(gp, y)) +
>    geom_point() +
>    geom_point(data = ds, aes(y = mean), colour = 'red', size = 3)
> print(p)
>
> And this now works.
>
> Cheers,
>
> Hugh
>
>
> On 02/03/17 13:42, Richard M. Heiberger wrote:
> > You need the print() statement.  See FAQ  7.22 in file
> > system.file("../../doc/FAQ")
> >
> >
> > 7.22 Why do lattice/trellis graphics not work?
> > ==============================================
> >
> > The most likely reason is that you forgot to tell R to display the
> > graph.  Lattice functions such as 'xyplot()' create a graph object, but
> > do not display it (the same is true of *ggplot2*
> > (https://CRAN.R-project.org/package=ggplot2) graphics, and Trellis
> > graphics in S-PLUS).  The 'print()' method for the graph object produces
> > the actual display.  When you use these functions interactively at the
> > command line, the result is automatically printed, but in 'source()' or
> > inside your own functions you will need an explicit 'print()' statement.
> >
> > On Thu, Mar 2, 2017 at 8:37 AM, Hugh Morgan <h.morgan at har.mrc.ac.uk>
> wrote:
> >> Hi All,
> >>
> >> I am having trouble outputting ggplot2 graphics to pdf as part of a
> >> script.  It works if when I pipe the script into R or if I type the
> >> commands directly into the terminal, but not if I load it using the
> >> source(..) command.  In this case the outputted pdf is always size 3611,
> >> and it fails to open with the error "This document contains no pages".
> >>
> >> As an example I wrap the create pdf commands around the 1st example in
> >> ?ggplot:
> >>
> >> $ cat test.R
> >>
> >> library(ggplot2)
> >>
> >> pdf("test.pdf")
> >>
> >> df <- data.frame(
> >>    gp = factor(rep(letters[1:3], each = 10)),
> >>    y = rnorm(30)
> >> )
> >> ds <- plyr::ddply(df, "gp", plyr::summarise, mean = mean(y), sd = sd(y))
> >> ggplot(df, aes(gp, y)) +
> >>    geom_point() +
> >>    geom_point(data = ds, aes(y = mean), colour = 'red', size = 3)
> >>
> >> dev.off()
> >>
> >> Piping it into R works:
> >>
> >> $ R --no-save < test.R
> >>
> >> ...
> >>
> >> $ ll test.pdf
> >>
> >> -rw-rw-r-- 1 user group 4842 Mar  2 13:18 test.pdf
> >>
> >> This file opens fine and has a graphic.  If I repeat the process using
> >> source():
> >>
> >> $ R --no-save
> >>
> >> R version 3.3.2 (2016-10-31) -- "Sincere Pumpkin Patch"
> >> ...
> >>
> >>> source("test.R")
> >>>
> >> $ ll test.pdf
> >> -rw-rw-r-- 1 user group 3611 Mar  2 13:25 test.pdf
> >>
> >> This file fails to open, and always has the size 3611.
> >>
> >> Any help appreciated,
> >>
> >> Hugh
> >>
> >>
> >>
> >> This email may have a PROTECTIVE MARKING, for an explanation please see:
> >>
> http://www.mrc.ac.uk/About/Informationandstandards/Documentmarking/index.htm
> >>
> >> ______________________________________________
> >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >> https://stat.ethz.ch/mailman/listinfo/r-help
> >> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> >> and provide commented, minimal, self-contained, reproducible code.
>
>
> This email may have a PROTECTIVE MARKING, for an explanation please see:
> http://www.mrc.ac.uk/About/Informationandstandards/Documentmarking/index.htm
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

	[[alternative HTML version deleted]]